Five things to know about North Korea's planned nuclear test

By Jethro Mullen, CNN

Updated 12:40 AM ET, Tue February 12, 2013

Chat with us in Facebook Messenger. Find out what's happening in the world as it unfolds.

Photos:Kim Jong Un and North Korea's military

North Korean leader Kim Jong Un meets with North Korea's first female fighter jet pilots in this undated photo released by the country's state media on Monday, June 22. He called the women "heroes of Korea" and "flowers of the sky."

Hide Caption

1 of 55

Photos:Kim Jong Un and North Korea's military

Kim stands on the snow-covered top of Mount Paektu in North Korea in a photo taken by North Korean newspaper Rodong Sinmun on April 18 and released the next day by South Korean news agency Yonhap. Kim scaled the country's highest mountain, North Korean state-run media reported, arriving at the summit to tell soldiers that the hike provides mental energy more powerful than nuclear weapons.

Hide Caption

2 of 55

Photos:Kim Jong Un and North Korea's military

Kim Jong Un, center, poses with soldiers on the snow-covered top of Mount Paektu in an April 18 photo released by South Korean news agency Yonhap.

Hide Caption

3 of 55

Photos:Kim Jong Un and North Korea's military

Kim visits the Kumsusan Palace of the Sun in Pyongyang, North Korea, on April 15 to celebrate the 103rd birth anniversary of his grandfather, North Korean founder Kim Il Sung.

Hide Caption

4 of 55

Photos:Kim Jong Un and North Korea's military

Kim inspects a drill for seizing an island at an undisclosed location in North Korea in an undated picture released by North Korea's official Korean Central News Agency on February 21.

Hide Caption

5 of 55

Photos:Kim Jong Un and North Korea's military

Kim speaks during a meeting of the Political Bureau of the Central Committee of the Workers' Party of Korea in Pyongyang, North Korea, in this photo released February 19 by the state-run Korean Central News Agency.

Hide Caption

6 of 55

Photos:Kim Jong Un and North Korea's military

A picture released by the North Korean Central News Agency shows North Korean leader Kim Jong Un appearing without his cane at an event with military commanders in Pyongyang on Tuesday, November 4. Kim, who recently disappeared from public view for about six weeks, had a cyst removed from his right ankle, a lawmaker told CNN.

Hide Caption

7 of 55

Photos:Kim Jong Un and North Korea's military

Kim is seen walking with a cane in this image released Thursday, October 30, by the state-run Korean Central News Agency.

Hide Caption

8 of 55

Photos:Kim Jong Un and North Korea's military

Kim sits in the pilot's seat of a fighter jet during the inspection.

Hide Caption

9 of 55

Photos:Kim Jong Un and North Korea's military

This undated photo, released Tuesday, October 14, by the KCNA, shows Kim inspecting a housing complex in Pyongyang, North Korea. International speculation about Kim went into overdrive after he failed to attend events on Friday, October 10, the 65th anniversary of the Workers' Party. He hadn't been seen in public since he reportedly attended a concert with his wife on September 3.

Hide Caption

10 of 55

Photos:Kim Jong Un and North Korea's military

A picture released by the KCNA shows Kim and his wife watching a performance by the Moranbong Band on Wednesday, September 3, in Pyongyang.

Hide Caption

11 of 55

Photos:Kim Jong Un and North Korea's military

Kim tours a front-line military unit in this image released Wednesday, July 16, by the KCNA.

Hide Caption

12 of 55

Photos:Kim Jong Un and North Korea's military

Kim poses for a photo as he oversees a tactical rocket-firing drill in June.

Hide Caption

13 of 55

Photos:Kim Jong Un and North Korea's military

Kim watches a tactical rocket-firing drill in June.

Hide Caption

14 of 55

Photos:Kim Jong Un and North Korea's military

A North Korean soldier patrols the bank of the Yalu River, which separates the North Korean town of Sinuiju from the Chinese border town of Dandong, on Saturday, April 26.

Hide Caption

15 of 55

Photos:Kim Jong Un and North Korea's military

In this photo released Thursday, April 24, by the Korean Central News Agency, Kim smiles with female soldiers after inspecting a rocket-launching drill at an undisclosed location.

Hide Caption

16 of 55

Photos:Kim Jong Un and North Korea's military

A picture released Tuesday, March 18, by the KCNA shows Kim attending a shooting practice at a military academy in Pyongyang.

Hide Caption

17 of 55

Photos:Kim Jong Un and North Korea's military

A North Korean soldier uses binoculars on Thursday, February 6, to look at South Korea from the border village of Panmunjom, which has separated the two Koreas since the Korean War.

Hide Caption

18 of 55

Photos:Kim Jong Un and North Korea's military

A North Korean soldier kicks a pole along the banks of the Yalu River on Tuesday, February 4.

Hide Caption

19 of 55

Photos:Kim Jong Un and North Korea's military

A photo released by the KCNA on Thursday, January 23, shows the North Korean leader inspecting an army unit during a winter drill.

Hide Caption

20 of 55

Photos:Kim Jong Un and North Korea's military

Kim inspects the command of an army unit in this undated photo released Sunday, January 12, by the KCNA.

Hide Caption

21 of 55

Photos:Kim Jong Un and North Korea's military

Kim visits an army unit in this undated photo.

Hide Caption

22 of 55

Photos:Kim Jong Un and North Korea's military

Kim inspects a military factory in this undated picture released by the KCNA in May 2013.

Hide Caption

23 of 55

Photos:Kim Jong Un and North Korea's military

Kim visits the Ministry of People's Security in 2013 as part of the country's May Day celebrations.

Hide Caption

24 of 55

Photos:Kim Jong Un and North Korea's military

A North Korean soldier, near Sinuiju, gestures to stop photographers from taking photos in April 2013.

Hide Caption

25 of 55

Photos:Kim Jong Un and North Korea's military

North Korean soldiers patrol near the Yalu River in April 2013.

Hide Caption

26 of 55

Photos:Kim Jong Un and North Korea's military

Kim is briefed by his generals in this undated photo. On the wall is a map titled "Plan for the strategic forces to target mainland U.S."

Hide Caption

27 of 55

Photos:Kim Jong Un and North Korea's military

Kim works during a briefing in this undated photo.

Hide Caption

28 of 55

Photos:Kim Jong Un and North Korea's military

In this KCNA photo, Kim inspects naval drills at an undisclosed location on North Korea's east coast in March 2013.

Hide Caption

29 of 55

Photos:Kim Jong Un and North Korea's military

Kim, with North Korean soldiers, makes his way to an observation post in March 2013.

Hide Caption

30 of 55

Photos:Kim Jong Un and North Korea's military

Kim uses a pair of binoculars to look south from the Jangjae Islet Defense Detachment, near South Korea's Taeyonphyong Island, in March 2013.

Hide Caption

31 of 55

Photos:Kim Jong Un and North Korea's military

Kim is greeted by a soldier's family as he inspects the Jangjae Islet Defense Detachment in March 2013.

Hide Caption

32 of 55

Photos:Kim Jong Un and North Korea's military

Kim is surrounded by soldiers during a visit to the Mu Islet Hero Defense Detachment, also near Taeyonphyong Island, in March 2013.

Hide Caption

33 of 55

Photos:Kim Jong Un and North Korea's military

Kim arrives at Jangjae Islet by boat to meet with soldiers of the Jangjae Islet Defense Detachment in March 2013.

Hide Caption

34 of 55

Photos:Kim Jong Un and North Korea's military

Soldiers in the North Korean army train at an undisclosed location in March 2013.

Hide Caption

35 of 55

Photos:Kim Jong Un and North Korea's military

In a photo released by the official North Korean news agency in December 2012, Kim celebrates a rocket's launch with staff from the satellite control center in Pyongyang.

Hide Caption

36 of 55

Photos:Kim Jong Un and North Korea's military

Kim, center, poses in this undated picture released by North Korea's official news agency in November 2012.

Hide Caption

37 of 55

Photos:Kim Jong Un and North Korea's military

Kim visits the Rungna People's Pleasure Ground, under construction in Pyongyang, in a photo released in July 2012 by the KCNA.

Hide Caption

38 of 55

Photos:Kim Jong Un and North Korea's military

A crowd watches as statues of North Korean founder Kim Il Sung and his son Kim Jong Il are unveiled during a ceremony in Pyongyang in April 2012.

Hide Caption

39 of 55

Photos:Kim Jong Un and North Korea's military

A North Korean soldier stands guard in front of an UNHA III rocket at the Tangachai-ri Space Center in April 2012.

Hide Caption

40 of 55

Photos:Kim Jong Un and North Korea's military

In April 2012, Pyongyang launched a long-range rocket that broke apart and fell into the sea. Here, the UNHA III rocket is pictured on its launch pad in Tang Chung Ri, North Korea.

Hide Caption

41 of 55

Photos:Kim Jong Un and North Korea's military

– A closer look at the UNHA III rocket on its launch pad in Tang Chung Ri, North Korea.

Hide Caption

42 of 55

Photos:Kim Jong Un and North Korea's military

A military vehicle participates in a parade in Pyongyang in April 2012.

Hide Caption

43 of 55

Photos:Kim Jong Un and North Korea's military

North Korean soldiers relax at the end of an official ceremony attended by leader Kim Jong Un at a stadium in Pyongyang in April 2012.

Hide Caption

44 of 55

Photos:Kim Jong Un and North Korea's military

Kim Jong Un applauds as he watches a military parade in Pyongyang in April 2012.

Hide Caption

45 of 55

Photos:Kim Jong Un and North Korea's military

A North Korean soldier stands on a balcony in Pyongyang in April 2012.

Hide Caption

46 of 55

Photos:Kim Jong Un and North Korea's military

North Korean soldiers march during a military parade in Pyongyang in April 2012.

Hide Caption

47 of 55

Photos:Kim Jong Un and North Korea's military

Soldiers board a bus outside a theater in Pyongyang in April 2012.

Hide Caption

48 of 55

Photos:Kim Jong Un and North Korea's military

North Korean performers sit below a screen showing images of leader Kim Jong Un in Pyongyang in April 2012.

Hide Caption

49 of 55

Photos:Kim Jong Un and North Korea's military

North Korean soldiers salute during a military parade in Pyongyang in April 2012.

Hide Caption

50 of 55

Photos:Kim Jong Un and North Korea's military

North Korean soldiers listen to a speech during an official ceremony attended by leader Kim Jong Un at a stadium in Pyongyang in April 2012.

Hide Caption

51 of 55

Photos:Kim Jong Un and North Korea's military

Members of a North Korean military band gather following an official ceremony at the Kim Il Sung stadium in Pyongyang in April 2012.

Hide Caption

52 of 55

Photos:Kim Jong Un and North Korea's military

North Korean military personnel watch a performance in Pyongyang in April 2012.

Hide Caption

53 of 55

Photos:Kim Jong Un and North Korea's military

A North Korean controller is seen along the railway line between the Pyongyang and North Pyongan provinces in April 2012.

Hide Caption

54 of 55

Photos:Kim Jong Un and North Korea's military

A North Korean military honor guard stands at attention at Pyongyang's airport in May 2001.

Hide Caption

55 of 55

Story highlights

North Korea has vowed to carry out a "higher level" test

Experts and officials say it could take place at any time

Opinions vary on exactly what kind of test it may carry out

Another nuclear test is likely to further strain relations in East Asia

North Korea's plans for a new nuclear test, like most things that happen inside the reclusive state, are shrouded in mystery. But that's not stopping analysts and officials from making some informed guesses about what's going on.

Why is North Korea planning to conduct a nuclear test?

The North says the "higher level" test is part of its military deterrent in its confrontation with the United States, which it describes as "the sworn enemy of the Korean people."

Its declaration that it would carry out the test came just two days after the United Nations Security Council voted in favor of imposing broader sanctions on the regime in response to Pyongyang's long-range rocket launch in December that was widely viewed as a test of ballistic missile technology.

The pattern of events is similar to the lead-up to the previous nuclear tests North Korea carried out in 2006 and 2009.

JUST WATCHED

Region braces for North Korea nuke test

MUST WATCH

Kim Jong Un appears likely to shrug off pressure from most of the international community, including North Korea's main ally, China, and go ahead with a third test.

"Neither the prospect of stronger sanctions, nor the growing discontent of Russia and China with his behavior, appears to deter North Korea's young leader," George Lopez, professor of peace studies at the Kroc Institute, University of Notre Dame, wrote in an opinion article this week for CNN.

Under the North's power-driven ideology of songun, or "military first," the punishment meted out last month by the U.N. Security Council requires a strong response, according to Daniel Pinkston, senior analyst for the International Crisis Group covering Northeast Asia.

North Korea "sees international law, international institutions, collective security, arms control and any other cooperative arrangement as undesirable and as schemes to undermine their national security," Pinkston said in a recent blog post.

A new test will also give North Korea a chance to underscore advances in its nuclear program, potentially moving it closer to a nuclear weapon that it can mount on a long-range missile.

"To make its nuclear arsenal more menacing and provide the deterrent power Pyongyang's vitriolic pronouncements are aimed to achieve, North Korea must demonstrate that it can deliver the weapons on missiles at a distance," Siegfried Hecker, a Stanford University professor who has visited North Korean nuclear facilities, wrote in an article for Foreign Policy this week.

Given that North Korea is one of the most isolated, secretive regimes on the planet, one that views much of the rest of the world with suspicion, getting a clear idea of what exactly it plans to do when is often far from straightforward.

Its announcement last month that it would go ahead with a nuclear test didn't provide a time-frame, so analysts and government officials around the globe are interpreting satellite images of the test zone and parsing the language in state media reports for clues.

Most of them agree that North Korea is technically ready and could carry out a test at any time. The question is when the top leaders in Pyongyang will give the political green light to go ahead with a move that is likely to further sour relations with the country's Asian neighbors and the United States.

"I think by their political calculations, this is where they're going to have, so to say, the most bang for the buck and make it most effective for what they want to try to accomplish," said Philip Yun, executive director of the Ploughshares Fund, a U.S.-based foundation that seeks to stop the spread of nuclear weapons.

Yun said this week that North Korea's recent statements suggest a test is "imminent."

The test is expected to take place underground at the North's Punggye-ri nuclear facility, and the first indications that a test has taken place are likely to show up on earthquake-monitoring equipment.

The area around Punggye-ri has little or no history of earthquakes or natural seismic hazards, according to U.S. Geological Survey (USGS) maps. But the previous test, in 2009, registered as a seismic event with a magnitude between 4 and 5.

JUST WATCHED

North Korea threatens new nuclear test

MUST WATCH

JUST WATCHED

North Korea move in 'defiance' of U.N.?

MUST WATCH

North Korea move in 'defiance' of U.N.?02:21

Besides earthquake-monitoring organizations like the USGS, the Comprehensive Test-Ban Treaty Organization in Vienna, has a network of seismic, sonar and radiation instruments designed to pick up nuclear tests. It also has sensors that can detect gases that may leak into the atmosphere from the explosion.

But determining the sophistication of the nuclear device, and what kind of material -- plutonium or uranium -- was used, will be considerably more difficult, experts say.

At some point, North Korea is likely to announce that the explosion has taken place.

"Pyongyang will almost certainly claim that the test was successful and will tout its sophistication. It will be difficult to distinguish truth from propaganda, but experience shows there is often a nugget of truth in North Korea's claims," Stanford's Hecker says.

What stage will North Korea's nuclear weapons program be at following a new test?

With hard facts about the test so scarce, analysts are busy theorizing what exactly North Korea means when it says the test will be of a "higher level."

There is a widespread expectation that it will involve the use of highly enriched uranium, whereas the country's two previous tests are understood to have involved plutonium-based devices.

"A successful uranium test indicates that Pyongyang has advanced centrifuge technologies and related support systems," Notre Dame's Lopez said. "It means that North Korea, if left unchecked, can both produce and export such material."

In an article for the Bulletin of the Atomic Scientists last year, Hecker and another analyst, Frank Pabian, speculated that North Korea could test two devices at the same time, one using plutonium and the other uranium.

"Two detonations will yield much more technical information than one, and they will be no more damaging politically than if North Korea conducted a single test," they wrote.

Some observers have even suggested that Pyongyang could make an early attempt at testing a thermonuclear device, which uses nuclear fusion to create a more powerful explosion. But others say they don't believe the North has that ability within its grasp yet.

In any case, the test is expected to take North Korea closer to having a nuclear weapon it can direct at its enemies. But actually achieving that goal still remains a longer-term effort, according to Joseph Cirincione, president of the Ploughshares Fund.

"I still think we're years away from North Korea having a capability to deliver a nuclear warhead on a missile even to a country as close as Japan or South Korea," Cirincione said recently. "And they're even further away from having a long-range missile that could hit the United States."

What are the consequences likely to be?

The region is already braced for the test to take place, and countries like the United States, South Korea and Japan are already preparing their response.

John Kerry, the new U.S. Secretary of State, spoke to his counterparts in Tokyo and Seoul by phone on Sunday, and all of three of them agreed that the North must understand "that it will face significant consequences from the international community if it continues its provocative behavior," according to a summary of the calls from the U.S. State Department

A push for fresh condemnation and sanctions from the U.N. Security Council is likely, but whether or not the new measures have much bite depends on China.

In the event of a new nuclear test, Beijing is likely "reduce its assistance to North Korea," the the state-run Chinese newspaper Global Times said in an editorial last month.

But it added that "if the U.S., Japan and South Korea promote extreme U.N. sanctions on North Korea, China will resolutely stop them and force them to amend these draft resolutions."

Fundamentally, analysts say, a new test won't upend the geopolitical situation in Northeast Asia. But it will seriously harm the chances of any meaningful dialog between Pyongyang, Seoul and Washington in the near future.

"It will signal that the new regime, like its predecessors, has chosen bombs over electricity" for its impoverished population, Hecker wrote.

Another test also increases concerns about where North Korea's nuclear material will end up in the long term, either because it decides to sell it or in the event of a collapse of the regime, according to Yun of the Ploughshares Fund.

"That's something that we really have to be concerned about," he said.